One Solution collect form web for “docker pull using puppet not working”

If you look at the error, it’s saying that Authentication is required.. This could be the user that Puppet is running the docker exec as has different permissions that your default user.

Have you thought about using the Docker module? It means you can perform the actions you want with, plus there’s a lot of community support, and it makes the Docker actions idempotent so you won’t get the commands running multiple times if not needed.